A vehicle includes an ignition switch. For example, the ignition switch includes an ignition rotor. A vehicle key is inserted into the ignition rotor through a key cylinder. In accordance with positions of the ignition rotor, the ignition switch starts and stops the engine and activates and deactivates electric components of the vehicle.
To improve vehicle safety, an ignition switch may be used together with a key interlock mechanism that prevents a vehicle key from being removed when the vehicle is traveling. Japanese Laid-Open Patent Publication No. 2003-343406 describes a key interlock mechanism that includes a camshaft, which rotates integrally with an ignition rotor.
However, the structure described in the above publication separates the ignition switch and the key interlock mechanism. Such a structure needs to obtain space in the vehicle for each of the ignition switch and the key interlock mechanism. This enlarges the area occupied by the key interlock mechanism in the vehicle.